[analyzer] This implements potential undefbehavior.ZeroAllocDereference checker.

TODO: support realloc(). Currently it is not possible due to the present realloc() handling. Currently RegionState is not being attached to realloc() in case of a zero Size argument. 
llvm-svn: 234889

1 files changed, 12 insertions, 1 deletions

diff --git a/clang/test/Analysis/Malloc+MismatchedDeallocator_intersections.cpp b/clang/test/Analysis/Malloc+MismatchedDeallocator_intersections.cpp
index 639790d31a9..bca223b6e04 100644
--- a/clang/test/Analysis/Malloc+MismatchedDeallocator_intersections.cpp
+++ b/clang/test/Analysis/Malloc+MismatchedDeallocator_intersections.cpp
@@ -24,5 +24,16 @@ void testNewDeleteNoWarn() {
 
   int *p4 = new int;
   delete p4;
-  int j = *p4; // no-warning  
+  int j = *p4; // no-warning
+}
+
+void testUseZeroAllocNoWarn() {
+  int *p1 = (int *)operator new(0);
+  *p1 = 1; // no-warning
+
+  int *p2 = (int *)operator new[](0);
+  p2[0] = 1; // no-warning
+
+  int *p3 = new int[0];
+  p3[0] = 1; // no-warning
 }